Protective apparatus for compensator-dynamos.



No- 880,812. PATENTED SEPT.-11, 1906. H. H. WAIT. PROTECTIVE APPARATUSFOR GOMPENSATOR DYNAMOS.

APPLICATION FILED .TAN.18, 1904.

4 SHEETS-SHEET 1.

PATENTED SEPT. 11, 1906.

H. H. WAIT. PROTECTIVE APPARATUS FOR COMPENSATOR DYNAMOS;

APPLICATION FILED JAKJB, 1904.

4 SHEETS-SHEET 2.

No- 830,812. PATENTED SEPT.11, 1906. H. H. WAIT. PROTECTIVE APPARATUSFOR COMPBNSATOR DYNAMOS:

APPLICATION FILED JAN. 18. 1904.

4 SHEETS-SHEET s.

uni-nu wz ir'zassea' i V 220M227: 7 I

wary/7.71656,

' point where it near HENRY H. WAIT, OF CHICAGO, ILLINOIS, ASSIGrNOR TOWESTERN ELECTRIC COMPANY, OF CHI OF ILLINOIS.

CAGO, ILLINOIS, A CORPORATION PROTECTIVE APPARATUS FORCOMPENSATOR-DYNAMOSt Specification of Letters Patent.

Patented Sept. 11, 1906.

Application am January 18,1904. sum Ho. 189.411.

To all whom it may concern:

Beit known that I, HENRY HQ WAIT, a citizen of the United States,residing at Chicago, in the county of Cook and State of Illinois, haveinvented a certain. new and useful Improvement in Protective Apparatusfor Compensator Dynamos, of which the following is a full, clear,concise, and exact description.

' My invention relates to a compensating system of electricaldistribution, such as the so-called three-Wire system, and more particularly toa system in which compoundwound com ensator-dynamos areemployed. The series field-windings of such compensa tors are soconnected as to partially neutralize the field created by theshunt-winding of the machine which at the time is running as a motor,this arrangement resulting in -a closer compensation than would bepossible with a simple shunt-wound compensator; but while thecompound-wound machine is better than the shunt-wound with res ect tocloseness of regulation it has the disa vantage that if an abnormallheavy overload is thrown on one side of t e system the current flowingthrough the series winding of the machine whose armature is connectedacross the other side of the system may increase to a field produced bythe shunt-winding. As the machine is at this time running as a motor,the result of the weakening of its field is to cause a tendency for themachine to race, thereb driving the generator on theother side 0 thesystem atan abnormally high speed, andlso tending to increase the'loadon. t

e generator, which still further augments the overload on the comensating machine and weakens the series fie d.

In accordance with my invention I provide an automatic circuit-closingswitch actuated when the current in the circuit increases beyond acertain predetermined amount to short-circuit the series field-windingsand allow the compensatorsto runas simple shuntwound machines. 1

I will describe my invention more particularly by reference to theaccompanying drawin?; in which- Y re 1 is a diagram showing a system inwhic three sets of compound-wound compensating machines are connected inmultipie with an automat c circuit-closing switch y or quite neutralizesthe for short-circuiting the series field-windings, said switch havingthree magnets, the switch being actuated when the current in either Fig.2 shows the a plication of'the invention to a single set 0 compensatingmachines. Fi 3 is a front elevatlon of the automatic switch used withthe system shown in Fig. 2. Fig. 4 is a side elevation of said switch,and Figs. 5 and 6 are diagrams illustrating my in vention embodied incompensator systems of .sli htlyrmodified form'. I

j he same characters of reference are used to designate the same partswherever they are shown. 7

Referring first to Figs. 3 and 4, a doublepole knife-switch having itsblades a a pivoted at a a, is normall held in an open position, as shownin dotte lines in Fig. 4, by a detent I), carried upon a horizontalrocking shaft 0. A spring-impelled plunger '11 is adapted when theswitch is released b the detent to give it an outward push, suc that itwill swing down into the closed position, as shown in full lines. Threetri arms or triggers b b b are ri 'dly carried y ,the rocking shaft 0,where y said shaft ma be rocked to raise the detent and release t eswitch b actuating any one of said triggers. Sai triggers are arrangedto be independently actuated 0 said magnets conslsts o a heavy-coiledcopper con uctor encircling an 11'011 core, and a pivoted ironarmature-lever f, mounted in position to be attracted by said core. Thearmature-lever of each magnet carries a trip 7', the beveled ace whereofis adapted to engage and move the projecting end of the corres ondingtri er when the armature-lever is di'awn u enever the current in eitherof the coi s e e e rises above the redetermined value, t e correspondingtrigger will detent b, whereby' the switch a will be releasedautomatically and close itself.

Referring now to Fig.1, the three-wire system. shown is organized andequipped in a well-known manner, except that an automatic switch a, suchas shown imFi s. 3 and 4, is provided for short-circuiting t e seriesfield-windings g g of the several multiple compensators. .Currentisderived from the mains 5 6 to supply the lamps or translating magnetrises above the predetermined value.

be actuated to rock the shaft 0 and raise the b electroma ets e e e, resectivel Each gn Y devices b h, which are connected between said mains,respectively, and a compensating conductor 11. Three sets ofcompoundwound compensators are shown, each set comprising twodynamomachines D D the armatures whereof are connected in series acrossthe mains 5 6. The armatures of machines D and D are mechanicallyconnected to rotate together, and in practice they are usually mountedon the same shaft. It isunderstood, of course, that in a compensatingsystem the current is supplied to the mains 5 6 by a central generator Gand that the compensator-dynamos D D are mechanically coupled andelectrically connected between the main conductors, respectively, andthe com ensating conductor. When one side of such a system is loadedmore than the other, one of the compensatordynamos will be driven by theother, which is run as a motor, to sup ly-additional current to theoverloaded side of the system.

.The compensating conductor 7 is connected through the magnet-coils e 12'e respectively, of the automatic switch in multiple to the middlepoints between each pair of armatures of the three compensator sets.Each compensator is provided with shunt field-windings 1c 7c and seriesfield-windings g g; but the switch a is adapted when closed to.short-circuit all the series fields and connect the armatures direct tothe mains 5 6. The usual switches s s .are indicated for controlling thecircuits of the several machines.

Fig. 2 shows the same circuit arrangements as Fig. 1, but for a singlepair of compensators, and the same reference characters are applied tocorresponding parts.

In the operation of the system the switch a is normally open, leavingthe series fieldwindings of the compensators in circuit; but

if one side or the other of the system should be abnormally overloadedone or more of the magnets e e 6?, according to circumstances, willreceive suflicient current V raise the corresponding armature untiltltrip carried thereby engages the trigger, and so .ocks the shaft 0 torelease the switch a, which automatically closes and short-circuits theseries fields, so preventing the racing of the machines and othertroubles which would otherwise result. Of course the operation of theautomatic switch should serve as a warning, and steps should be taken Iat once to e( ualize the load on the system.

In Fig. 5 have shown the magnet-coil e for operating the switch aincluded directly in the circuit of the series coils of two dynamos,while in Fig. 6 I have illustrated vtwo dynamos each provided with amagnet-coil e included in series with the armature and series fieldthereof. With either of these arrangements the magnet-coil e willoperate to close the automatic switch controlled thereby whenever thecurrent in the series due to short-circuits in the armature or toabnormal conditions which may arise in the external circuit of thesystem.

' Having thus described my invention, I claim- 1. In a compensatingsystem of electrical distribution, the combination with the maingenerator and compensator-dynamos provided with compound windings, of anelectromagnetic switch responsive to excessive current through one sideof the system, adapted in'its response to render inoperative the seriesfield-windings of said compensator-dynamos.

2. In a com ensating system of electrical distribution, tie combinationwith a main generator, of sets of compound-wound compensator-dynamosconnected in multiple between the distributing-mains and thecompensating. conductor of the system, a selfclosing'switch-adapted toshort-circuit the series field-windings of all of saidcompensator-dynamos,.magnet-windings in circuit between saidcompensating conductor and each of said dynamos, and means responsive toan excessive current in either of said magnet-windings for causing theclosure of said switch.

3. The combination with a number of pairs of compensator-dynamos in acom ensating system of electrical distribution, 0 a shortcirc'uitingswitch controlling the field-windings of said dynamos, said switchcomprising pivoted switch-blades and contacts therefor,

. a detent normally holding the switch'open, a

spring for closing the switch when released, e ectromagnets connected torespond to excessive current in one side of the system, and armaturesfor said electromagnets, arranged to disengage said. detent and releasethe switch, substantially as and for'the purpose set forth.

4. In a com ensating system of electrical distribution, t e combinationwith a main generator, main distributing conductors connected with theterminals of said generator, a. neutral or compensating conductor andtranslating devices con'nected'between said compensating conductor andsaid main conductors respectively, of compensator-d namos mechanicallycoupled and electrical y connected between said main conductorsrespectively and said compensating conductor, said compensator-dynamosbeing .provided with compound windings, a switch adapted toshort-circuit the series field-windings of said dynamos, and meanscontrolled b the passage of excessive current in the circuit through oneof said dynamos to the compensating conductor, for actuating saidswitch.

5. The combination with a compensating system of electricaldistribution,comprising main conductors 5, 6, and a compensating conductor 7, ofcompensator-d amos mechanically coupled and electrical y connectedbetween said main conductors respectively and said compensatingconductor, said dynamos having compound field-windings, and means resonsive to an excessive current in the series eld-windings of saidcompensatordynamos for short-circuiting said windings, substantially asset forth.

6. The combination with a compensating system of-electrical distributioncomprising a main generator, main distributing-conductors connected withthe terminals of said enerator, a compensatin conductor, transatingdevices connected etween said compensating conductor and each of saidmain conductors,.a number of compensator-dynamo sets, each set comprisintwo dynamos mechanically coupled and e ectrically connected between themain conductors respectively and the compensating conductor, said HENRYH. WAIT.

.Witnessesi EDWIN H. SMYTIIE, IRVING MAcDoNALn.

